1. Field of the Invention
The present invention relates to a motion picture projection device such as a cine-projector, etc.
2. Description of the Prior Art
Nowadays, as a motion picture projector such as a cine-projector, etc., a so-called a sound projector which can reproduce picture image information and sound information simultaneously and a silent projector which can reproduce picture image information only are offered in the market.
One of the reasons for these sound projector and silent projector being offered is their prices and corresponding functions. That is, when a sound projector and a silent projector are compared, since a silent projector does not need to have a device for reproduction and recording of sound information to be built in, its structure becomes simple thus its production cost is lower than that of a sound projector, therefore it can be offered at a lower price than that of a sound projector. On the other hand, from a standpoint of a user who is to buy a projector, there is a person who wants to get a low priced projector which can at least reproduce picture image information only even if it can not reproduce sound information and picture image information simultaneously, while there is a different person who wants to buy a projector which can reproduce sound information and picture image information simultaneously even if its price is somewhat higher, thus such different types of projectors are offered to satisfy the needs of market.
As another reason therefor, as a film for projection, while there is a so-called sound film, there is also a silent film which has picture image information recorded thereon but has no sound information recorded thereon, and for a person who is using such silent film, a projector which has a sound recording and reproducing device built in is not only unnecessary, but is too heavy and too large in size as the projector has said sound recording and reproducing device built in, thus it is inconvenient for carrying and handling.
However, even a person who only has a silent projector, sometimes wishes to have both sound information and picture image information reproduced simultaneously and enjoy the same by using a sound film, but in that event his silent projector can not reproduce sound information, thus as a matter of course he is required to have a sound projector available. But, if a sound projector can be formed by using his silent projector, that is using his silent projector as a projection unit with minor modification and attaching a separate sound recording and reproducing unit thereto, then he does not have to buy a high-priced sound projector only for that special occasion of using a sound film, yet he can have said desired simultaneous reproduction done successfully, using an already available projector almost as it is, thus it is quite convenient in practical use.
Now a conventional sound projector and a conventional silent projector are made with no common features therebetween in manufacturing process, and are produced independently from each other. Therefore, component parts for a sound projector and those for a silent projector are made separately, thus production and maintenance of those component parts need to be done in a so-called small-lot multi-kinds production (maintenance) style, resulting in increased cost of the products for a manufacturer.
Particularly it is quite unreasonable both in operation efficiency and labor to have a silent projector assembling line and a sound projector assembling line separately provided for assembling of said component parts.
Therefore, for a manufacturer, it is desirable to have common component parts for a silent projector and a sound projector and to have a common assembling line therefor as much as possible.
That is, component parts for a silent projector and those for a sound projector are made common therebetween as much as possible, and at a same time an assembling line for projection units for sound projectors is provided in a middle of an assembling line of silent projectors, and on the other hand an assembling line for sound recording and reproducing units is provided separately, so that in the assembling line of sound projectors, said projection units and sound units are assembled together at its last process, then such projection arrangement and set up can enhance operating efficiency and save labor, thus cost of the products can be greatly reduced.